Electrorheological fluid structure with attached conductor and method of fabrication

ABSTRACT

A polymeric housing may have a channel defined therein. A first conductive trace may at least partially coincide with the channel. A first wire may have a first conductor surrounded by a first insulating jacket. The first conductor may be in electrical communication with the first conductive trace. A jacket bonding region of the first jacket may be welded to a housing bonding region of the housing. The jacket bonding region and the housing bonding region may be formed from a common type of polymer.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority to U.S. provisional patent applicationNo. 62/260,890, titled “ELECTRORHEOLOGICAL FLUID STRUCTURE WITH ATTACHEDCONDUCTOR AND METHOD OF FABRICATION” and filed Nov. 30, 2015.Application No. 62/260,890, in its entirety, is incorporated byreference herein.

BACKGROUND

Conventional articles of footwear generally include an upper and a solestructure. The upper provides a covering for the foot and securelypositions the foot relative to the sole structure. The sole structure issecured to a lower portion of the upper and is configured so as to bepositioned between the foot and the ground when a wearer is standing,walking, or running.

Conventional footwear is often designed with the goal of optimizing ashoe for a particular condition or set of conditions. For example,sports such as tennis and basketball require substantial side-to-sidemovements. Shoes designed for wear while playing such sports ofteninclude substantial reinforcement and/or support in regions thatexperience more force during sideways movements. As another example,running shoes are often designed for forward movement by a wearer in astraight line. Difficulties can arise when a shoe must be worn duringchanging conditions, or during multiple different types of movements.

SUMMARY

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the invention.

In at least some embodiments, an article may include a polymeric housinghaving a channel defined therein. A first conductive trace may at leastpartially coincide with the channel. A first wire may have a firstconductor surrounded by a first insulating jacket. The first conductormay be in electrical communication with the first conductive trace. Ajacket bonding region of the first jacket may be welded to a housingbonding region of the housing. The jacket bonding region and the housingbonding region may be formed from a common type of polymer.

Additional embodiments are described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Some embodiments are illustrated by way of example, and not by way oflimitation, in the figures of the accompanying drawings and in whichlike reference numerals refer to similar elements.

FIG. 1 is a medial side view of a shoe according to some embodiments.

FIG. 2A is a bottom view of the sole structure of the shoe of FIG. 1.

FIG. 2B is a bottom view of the sole structure of the shoe of FIG. 1,but with a forefoot outsole element and an incline adjuster removed.

FIG. 2C is a bottom view of the forefoot outsole element of the solestructure of the shoe of FIG. 1.

FIG. 3 is a partially exploded medial perspective view of the solestructure of the shoe of FIG. 1.

FIG. 4A is an enlarged top view of an incline adjuster of the shoe ofFIG. 1.

FIG. 4B is a rear edge view of the incline adjuster of FIG. 4A.

FIG. 5A is a top view of a bottom layer of the incline adjuster of FIG.4A.

FIG. 5B is a top view of a middle layer of the incline adjuster of FIG.4A.

FIG. 5C1 is a top view of a top layer of the incline adjuster of FIG.4A.

FIG. 5C2 is a bottom view of the top layer of the incline adjuster ofFIG. 4A.

FIG. 5C3 is a partial area cross-sectional view of the top layer of theincline adjuster of FIG. 4A.

FIG. 5D1 shows a first assembly operation in the fabrication of anincline adjuster according to some embodiments.

FIG. 5D2 shows a second assembly operation in the fabrication of anincline adjuster according to some embodiments.

FIG. 5D3 is a top view of a partially completed incline adjuster afterbonding of layers but prior to filling with electrorheological fluid.

FIGS. 5E1 and FIG. 5E2 are partially schematic area cross-sectionalviews taken from the locations indicated in FIG. 4A.

FIGS. 5E3 and FIG. 5E4 are partially schematic area cross-sectionalviews taken from the locations indicated in FIGS. 5E1 and 5E2,respectively.

FIGS. 5E5 through 5E10 are partially schematic area cross-sectionalviews, taken from locations similar to that indicated in FIG. 5E1 forFIG. 5E3, of attached wires according to additional embodiments.

FIGS. 5E11 and 5E12 are partially schematic area cross-sectional viewstaken from the locations indicated in FIG. 4A.

FIG. 6 is a block diagram showing electrical system components in theshoe of FIG. 1.

FIGS. 7A through 7D are partially schematic area cross-sectionaldiagrams showing operation of the incline adjuster of the shoe of FIG. 1when going from a minimum incline condition to a maximum inclinecondition.

FIG. 7E is a top view of the incline adjuster and a bottom plate of theshoe of FIG. 1, and showing the approximate locations of sectioninglines corresponding to the views of FIGS. 7A-7D.

FIGS. 8A and 8B are top views of two sides of a first RF welding toolaccording to some embodiments.

FIGS. 8C and 8D are top views of two sides of a second RF welding toolaccording to some embodiments.

FIG. 9 is a block diagram showing steps in a method according to someembodiments.

FIG. 10 is a partially schematic diagram showing an annular weldingoperation.

DETAILED DESCRIPTION

In various types of activities, it may be advantageous to change theshape of a shoe or shoe portion while a wearer of that shoe is runningor otherwise participating in the activity. In many runningcompetitions, for example, athletes race around a track having curvedportions, also known as “bends.” In some cases, particularly shorterevents such as 200 meter or 400 meter races, athletes may be running atsprint paces on a track bend. Running on a flat curve at a fast pace isbiomechanically inefficient, however, and may require awkward bodymovements. To counteract such effects, bends of some running tracks arebanked. This banking allows more efficient body movement and typicallyresults in faster running times. Tests have shown that similaradvantages can be achieved by altering the shape of a shoe. Inparticular, running on a flat track bend in a shoe having a footbed thatis inclined relative to the ground can mimic the benefits of running ona banked bend in a shoe having a non-inclined footbed. However, aninclined footbed is a disadvantage on straight portions of a runningtrack. Footwear that can provide an inclined footbed when running on abend and reduce or eliminate the incline when running on a straighttrack section would offer a significant advantage.

In footwear according to some embodiments, electrorheological (ER) fluidis used to change the shape of one or more shoe portions. ER fluidstypically comprise a non-conducting oil or other fluid in which verysmall particles are suspended. In some types of ER fluid, the particlesmay be have diameters of 5 microns or less and may be formed frompolystyrene or another polymer having a dipolar molecule. When anelectric field is imposed across the ER fluid, the viscosity of thefluid increases as the strength of that field increases. As described inmore detail below, this effect can be used to control transfer of fluidand modify the shape of a footwear component. Although track shoeembodiments are initially described, other embodiments include footwearintended for other sports or activities.

To assist and clarify subsequent description of various embodiments,various terms are defined herein. Unless context indicates otherwise,the following definitions apply throughout this specification (includingthe claims). “Shoe” and “article of footwear” are used interchangeablyto refer to an article intended for wear on a human foot. A shoe may ormay not enclose the entire foot of a wearer. For example, a shoe couldinclude a sandal-like upper that exposes large portions of a wearingfoot. The “interior” of a shoe refers to space that is occupied by awearer's foot when the shoe is worn. An interior side, surface, face, orother aspect of a shoe component refers to a side, surface, face orother aspect of that component that is (or will be) oriented toward theshoe interior in a completed shoe. An exterior side, surface, face orother aspect of a component refers to a side, surface, face or otheraspect of that component that is (or will be) oriented away from theshoe interior in the completed shoe. In some cases, the interior side,surface, face or other aspect of a component may have other elementsbetween that interior side, surface, face or other aspect and theinterior in the completed shoe. Similarly, an exterior side, surface,face or other aspect of a component may have other elements between thatexterior side, surface, face or other aspect and the space external tothe completed shoe.

Shoe elements can be described based on regions and/or anatomicalstructures of a human foot wearing that shoe, and by assuming that theinterior of the shoe generally conforms to and is otherwise properlysized for the wearing foot. A forefoot region of a foot includes theheads and bodies of the metatarsals, as well as the phalanges. Aforefoot element of a shoe is an element having one or more portionslocated under, over, to the lateral and/or medial side of, and/or infront of a wearer's forefoot (or portion thereof) when the shoe is worn.A midfoot region of a foot includes the cuboid, navicular, andcuneiforms, as well as the bases of the metatarsals. A midfoot elementof a shoe is an element having one or more portions located under, over,and/or to the lateral and/or medial side of a wearer's midfoot (orportion thereof) when the shoe is worn. A heel region of a foot includesthe talus and the calcaneus. A heel element of a shoe is an elementhaving one or more portions located under, to the lateral and/or medialside of, and/or behind a wearer's heel (or portion thereof) when theshoe is worn. The forefoot region may overlap with the midfoot region,as may the midfoot and heel regions.

Unless indicated otherwise, a longitudinal axis refers to a horizontalheel-toe axis along the center of the foot that is roughly parallel to aline along the second metatarsal and second phalanges. A transverse axisrefers to a horizontal axis across the foot that is generallyperpendicular to a longitudinal axis. A longitudinal direction isgenerally parallel to a longitudinal axis. A transverse direction isgenerally parallel to a transverse axis.

FIG. 1 is a medial side view of a track shoe 10 according to someembodiments. The lateral side of shoe 10 has a similar configuration andappearance, but is configured to correspond to a lateral side of awearer foot. Shoe 10 is configured for wear on a right foot and is partof a pair that includes a shoe (not shown) that is a mirror image ofshoe 10 and is configured for wear on a left foot.

Shoe 10 includes an upper 11 attached to a sole structure 12. Upper 11may be formed from any of various types or materials and have any of avariety of different constructions. In some embodiments, for example,upper 11 may be knitted as a single unit and may not include a bootie ofother type of liner. In some embodiments, upper 11 may be slip lasted bystitching bottom edges of upper 11 to enclose a foot-receiving interiorspace. In other embodiments, upper 11 may be lasted with a strobel or insome other manner. A battery assembly 13 is located in a rear heelregion of upper 11 and includes a battery that provides electrical powerto a controller. The controller is not visible in in FIG. 1, but isdescribed below in connection with other drawing figures.

Sole structure 12 includes a footbed 14, an outsole 15, and an inclineadjuster 16. Incline adjuster 16 is situated between outsole 15 andfootbed 14 in a forefoot region. As explained in more detail below,incline adjuster 16 includes a medial side fluid chamber that supports amedial forefoot portion of footbed 14, as well as a lateral side fluidchamber that supports a lateral forefoot portion of footbed 14. ER fluidmay be transferred between those chambers through a connecting transferchannel that is in fluid communication with the interiors of bothchambers. That fluid transfer may raise the height of one chamberrelative to the other chamber, resulting in an incline in a portion offootbed 14 located over the chambers. When further flow of ER fluidthrough the channel is interrupted, the incline is maintained until ERfluid flow is allowed to resume.

Outsole 15 forms the ground-contacting portion of sole structure 12. Inthe embodiment of shoe 10, outsole 15 includes a forward outsole section17 and a rear outsole section 18. The relationship of forward outsolesection 17 and rear outsole section 18 can be seen by comparing FIG. 2A,a bottom view of sole structure 12, and FIG. 2B, a bottom view of solestructure 12 with forefoot outsole section 17 and incline adjuster 16removed. FIG. 2C is a bottom view of forefoot outsole section 17 removedfrom sole structure 12. As seen in FIG. 2A, forward outsole section 17extends through forefoot and central midfoot regions of sole structure12 and tapers to a narrowed end 19. End 19 is attached to rear outsolesection 18 at a joint 20 located in the heel region. Rear outsolesection 18 extends over side midfoot regions and over the heel regionand is attached to footbed 14. Forward outsole section 17 is alsocoupled to footbed 14 by a fulcrum element and by the above-mentionedfluid chambers of incline adjuster 16. Forefoot outsole section 17pivots about a longitudinal axis L1 passing through joint 20 and throughthe forefoot fulcrum element. In particular, and as explained below,forefoot outsole section 17 rotates about axis L1 as a forefoot portionof footbed 14 inclines relative to forefoot outsole section 17.

Outsole 15 may be formed of a polymer or polymer composite and mayinclude rubber and/or other abrasion-resistant material onground-contacting surfaces. Traction elements 21 may be molded into orotherwise formed in the bottom of outsole 15. Forefoot outsole section17 may also include receptacles to hold one or more removable spikeelements 22. In other embodiments, outsole 15 may have a differentconfiguration.

Footbed 14 includes a midsole 25. In the embodiment of shoe 10, midsole25 has a size and a shape approximately corresponding to a human footoutline, is a single piece that extends the full length and width offootbed 14, and includes a contoured top surface 26 (shown in FIG. 3).The contour of top surface 26 is configured to generally correspond tothe shape of the plantar region of a human foot and to provide archsupport. Midsole 25 may be formed from ethylene vinyl acetate (EVA)and/or one or more other closed cell polymer foam materials. Midsole 25may also have pockets 27 and 28 formed therein to house a controller andother electronic components, as described below. Upwardly extendingmedial and lateral sides of rear outsole section 18 may also provideadditional medial and lateral side support to a wearer foot. In otherembodiments, a footbed may have a different configuration, e.g., amidsole may cover less than all of a footbed or may be entirely absent,and/or a footbed may include other components.

FIG. 3 is a partially exploded medial perspective view of sole structure12. Bottom support plate 29 is located in a plantar region of shoe 10.In the embodiment of shoe 10, bottom support plate 29 is attached to atop surface 30 of forward outsole section 17. Bottom support plate 29,which may be formed from a relatively stiff polymer or polymercomposite, helps to stiffen the forefoot region of forward outsolesection 17 and provide a stable base for incline adjuster 16. A medialforce-sensing resistor (FSR) 31 and a lateral FSR 32 are attached to atop surface 33 of bottom support plate 29. As explained below, FSRs 31and 32 provide outputs that help determine pressures within chambers ofincline adjuster 16.

Fulcrum element 34 is attached to top surface 33 of lower support plate29. Fulcrum element 34 is positioned between FSRs 31 and 32 in a frontportion of bottom support plate 29. Fulcrum element 34 may be formedfrom polyurethane, silicon rubber, EVA, or from one or more othermaterials that are generally incompressible under loads that result whena wearer of shoe 10 runs. Fulcrum element 34 provides resistance totransverse and longitudinal forces applied to the incline adjuster 16.

Incline adjuster 16 is attached to top surface 33 of lower support plate29. A medial fluid chamber 35 of incline adjuster 16 is positioned overmedial FSR 31. A lateral fluid chamber 36 of incline adjuster 16 ispositioned over lateral FSR 32. Incline adjuster 16 includes an aperture37 through which fulcrum element 34 extends. At least a portion offulcrum element 34 is positioned between chambers 35 and 36. Additionaldetails of incline adjuster 16 are discussed in connection withsubsequent drawing figures. A top support plate 41 is also located in aplantar region of shoe 10 and is positioned over incline adjuster 16. Inthe embodiment of shoe 10, top support plate 41 is generally alignedwith bottom support plate 29. Top support plate 41, which may also beformed from a relatively stiff polymer or polymer composite, provides astable and relatively non-deformable region against which inclineadjuster 16 may push, and which supports the forefoot region of footbed14.

A forefoot region portion of the midsole 25 underside is attached to thetop surface 42 of top support plate 41. Portions of the midsole 25underside in the heel and side midfoot regions are attached to a topsurface 43 of rear outsole section 18. End 19 of forward outsole section17 is attached to rear outsole section 18 behind the rear-most location44 of the front edge of section 18 so as to form joint 20. In someembodiments, end 19 may be a tab that slides into a slot formed insection 18 at or near location 44, and/or may be wedged between topsurface 43 and the underside of midsole 25.

Also shown in FIG. 3 are a DC-to-high-voltage-DC converter 45 and aprinted circuit board (PCB) 46 of a controller 47. Converter 45 convertsa low voltage DC electrical signal into a high voltage (e.g., 5000V) DCsignal that is applied to electrodes within incline adjuster 16. PCB 46includes one or more processors, memory and other components and isconfigured to control incline adjuster 16 through converter 45. PCB 46also receives inputs from FSRs 31 and 32 and receives electrical powerfrom battery unit 13. PCB 46 and converter 45 may be attached to the topsurface of forward outsole section 17 in a midfoot region 48, and mayalso rest within pockets 28 and 27, respectively, in the undersidemidsole 25. Wires 23 a and 24 a electrically connect converter 45 toincline adjuster 16. A terminal 23 b on a first end of wire 23 a isinserted into a connection passage 39 on the rear edge of inclineadjuster 16 and attached to a portion of a conductive trace projectinginto an access passage 39, as described in more detail below. A terminal24 b on a first end of wire 24 a is inserted into an access passage 40on the rear edge of incline adjuster 16 and attached to a portion of aseparate conductive trace projecting into passage 40, as described inmore detail below. In some embodiments, terminals 23 b and 24 b maysimply be portions of conductors of wires 23 a and 23 b that have beenexposed by removing insulating jacket material. In other embodiments,separate terminal structures may be added. Second ends of wires 23 a and24 a are connected to appropriate terminals of converter 45. Additionalsets of wires, not shown, connect converter 45 and PCB 46 and connectPCB 46 to battery assembly 13.

FIG. 4A is an enlarged top view of incline adjuster 16 and attachedwires 23 a and 24 a. FIG. 4B is a rear edge view of incline adjuster 16from the location indicated in FIG. 4A. Medial fluid chamber 35 is influid communication with lateral fluid chamber 36 through a fluidtransfer channel 51. An ER fluid fills chambers 35 and 36 and transferchannel 51. One example of an ER fluid that may be used in someembodiments is sold under the name “RheOil 4.0” by Fludicon GmbH,Landwehrstrasse 55, 64293 Darmstadt, Deutschland (Germany). In thepresent example, it is assumed that the top of incline adjuster 16 isformed by an opaque layer, and thus transfer channel 51 is indicated inFIG. 4A with broken lines.

Access passages 39 and 40 are similarly indicated in FIG. 4A with brokenlines. Terminals 23 b and 24 b have been inserted into passages 39 and40 and welded in place, as described in more detail below. As a resultof that welding, a rear portion of incline adjuster 16 around passages39 and 40 has been flattened to form a crimp 151. Within crimp 151,layer 54 has melted and sealed around the outer edges of wires 23 a and23 b. In at least some embodiments, wires 23 a and 24 a are attached toincline adjuster 16 prior to filling with ER fluid.

Transfer channel 51 has a serpentine shape so as to provide increasedsurface area for electrodes within channel 51 to create an electricalfield in fluid within channel 51. For example, and as seen in FIG. 4A,channel 51 includes three 180° curved sections joining other sections ofchannel 51 that cover the space between chambers 35 and 36. In someembodiments, transfer channel 51 may have a maximum height h (FIG. 4B)of 1 millimeter (mm), an average width (w) of 2 mm, and a minimum lengthalong the flow direction of at least 257 mm.

In some embodiments, height of the transfer channel may practically belimited to a range of at least 0.250 mm to not more than 3.3 mm. Anincline adjuster constructed of pliable material may be able to bendwith the shoe during use. Bending across the transfer channel locallydecreases the height at the point of bending. If sufficient allowance isnot made, the corresponding increase in electric field strength mayexceed the maximum dielectric strength of the ER fluid, causing theelectric field to collapse. In the extreme, electrodes could become soclose so as to actually touch, with the same resultant electric fieldcollapse.

The viscosity of ER fluid increases with the applied electric fieldstrength. The effect is non-linear and the optimum field strength is inthe range of 3 to 6 kilovolts per millimeter (kV/mm). The high-voltagedc-dc converter used to boost the 3 to 5 V of the battery may be limitedby physical size and safety considerations to less than 2 W or a maximumoutput voltage of less than or equal to 10 kV. To keep the electricfield strength within the desired range, the height of the transferchannel may therefore be limited in some embodiments to a maximum ofabout 3.3 mm (10 kV/3 kV/mm).

The width of the transfer channel may be practically limited to a rangeof at least 0.5 mm to not more than 4 mm. As explained below, an inclineadjuster may be constructed of 3 or more layers of thermal plasticurethane film. The layers of film may be bonded together with heat andpressure. During this bonding process, temperatures in portions of thematerials may exceed the glass transition temperature when melting so asto bond melted materials of adjoining layers. The pressure duringbonding inter-mixes the melted material, but may also extrude a portionof the melted material into the transfer channel preformed within themiddle spacer layer of the incline adjuster. The channel may thus bepartially filled by this material. At channel widths less than 0.5 mm,the proportion of the material extruded may be a large percentage of thechannel width, thereby restricting flow of the ER fluid.

The maximum width of the channel may be limited by the physical spacebetween the two chambers of the incline adjuster. If the channel iswide, the material within the middle layer may become thin andunsupported during construction, and walls of the channel may be easilydislodged. The equivalent series resistance of ER fluid will alsodecrease as channel width increases, which increases the powerconsumption. For a shoe size range down to M5.5 (US) the practical widthmay be limited to less than 4 mm.

The desired length of the transfer channel may be a function of themaximum pressure difference between chambers of the incline adjusterwhen in use. The longer the channel, the greater the pressure differencethat can be withstood. Optimum channel length may be applicationdependent and construction dependent and therefore may vary amongdifferent embodiments. A detriment of a long transfer channel is agreater restriction to fluid flow when the electric field is removed. Insome embodiments, practical limits of channel length are in the range of25 mm to 350 mm.

Incline adjuster 16 includes a medial side fill tab 117 and a lateralside fill tab 118. Tabs 117 and 118 respectively include fill channels119 and 120. After certain components of incline adjuster 16 have beenassembled and bonded, and as described below in further detail, ER fluidmay be injected into chambers 35 and 36 and into transfer channel 51through channel 119 and/or through channel 120. Crimps 125 and 126 maysubsequently be formed to close and seal channels 119 and 120.

In some embodiments, an incline adjuster may have a polymeric housing.As seen in FIG. 4B, the polymeric housing of incline adjuster 16 mayinclude a bottom layer 53, a middle/spacer layer 54, and a top layer 55.Bottom layer 53 forms the bottoms of chambers 35 and 36, the bottom oftransfer channel 51, the bottoms of access passages 39 and 40, and thebottoms of fill channels 119 and 120. Middle/spacer layer 54 includesopen spaces that form the side walls of chambers 35 and 36, the sidewalls of transfer channel 51, the side walls of fill channels 119 and120, and the side walls of passages 39 and 40. Top layer 55 includes twopockets. A medial side pocket 57 forms the top and upper sidewalls ofmedial chamber 35. A lateral side pocket 58 forms the top and uppersidewalls of lateral chamber 36. Other portions of top layer 55 form thetop of transfer channel 51, the tops of fill channels 119 and 120, andthe tops of passages 39 and 40. A bottom surface of middle layer 54 maybe welded or otherwise bonded to a portion of the top surface of bottomlayer 53. A top surface of middle layer 54 may be welded or otherwisebonded to a portion of the bottom surface of top layer 55.

The construction of incline adjuster 16 is further understood byreference to FIGS. 5A through 5E2. FIG. 5A is a top view of bottom layer53. Bottom layer 53 includes a flat panel 81 having a top surface 59.Except for an opening 60 that is part of fulcrum aperture 37, panel 81is a continuous sheet. Layer 53 further includes a continuous conductivetrace 116 formed on top surface 59. Trace 116 includes a bottomelectrode 61 and an extension 62. Electrode 61 is positioned to extendover the portion of layer 53 that forms the bottom of transfer channel51. As seen in more detail below, electrode 61 follows the path of andcoincides with channel 51. Extension 62 branches away from the path ofchannel 51 and towards the rear edge of bottom layer 53. As explained inmore detail below, extension 62 provides a location to electricallyconnect terminal 23 b (FIG. 3) to electrode 61. In some embodiments,conductive trace 116 is a span of conductive ink that has been printedonto surface 59. The conductive ink used to form conductive trace 116may be, e.g., an ink that comprises silver microparticles in a polymermatrix that includes thermoplastic polyurethane (TPU), and that bondswith TPU of panel 81 to form a flexible conductive layer. One example ofsuch an ink is PE872 stretchable conductor available from E.I. DuPont DeNemours and Company.

In some embodiments, panel 81 is formed from two separate inner andouter sheets of polymeric material that have been laminated together.The outer sheet may be a 0.4 mm sheet of TPU having a Shore A durometervalue of 85. An example of such a material includes a sheet formed fromTPU resin having part number A92P4637 and available from HuntsmanCorporation. In some embodiments, the outer sheet in panel 81 may be a0.5 mm sheet of polyester-based TPU having a Shore A durometer value of85. The inner sheet in panel 81 may be a 0.1 mm thick 2-layerpolyurethane/polyurethane sheet in which one of the sheet layers is ofhigher durometer than the other of those two layers. Examples of such2-layer of polyurethane/polyurethane sheets are commercially availablefrom Bemis Associates Inc.

In some embodiments, layer 53 may be fabricated in the following manner.Prior to forming panel 81, conductive trace 116 is screen printed orotherwise applied to the higher durometer face of the inner sheet. Thelower durometer face of the inner sheet may then be placed into contactwith an inner face of the outer sheet. The inner and outer sheets maythen be laminated together by applying heat and pressure. Bottom layer53 is then cut from the laminated sheets so that conductive trace 116 isin the proper location relative to outer edges and relative to opening60.

FIG. 5B is a top view of middle layer 54 showing top surface 63 ofmiddle layer 54. Middle layer 54 includes numerous open spaces thatextend from top surface 63 to the bottom surface of middle layer 54. Anopen space 64 is isolated from other open spaces in layer 54 and is partof fulcrum aperture 37. Open space 127 forms side walls of medial fluidchamber 35. Open space 128 forms side walls of lateral fluid chamber 36.Open space 129 is connected to open spaces 127 and 128 and forms sidewalls of channel 51. Open spaces 131 and 132 are respectively connectedto open spaces 127 and 128 and respectively form side walls of fillchannels 119 and 120. Open spaces 133 and 134, which are isolated fromeach other and from other open spaces in layer 54, respectively formsides walls of access passages 39 and 40. In some embodiments, middlelayer 54 is cut from a single sheet of TPU that is harder than TPU usedin layers 53 and 55. In some such embodiments, the TPU used for layer 54is 1.0 mm thick and has a Shore A durometer value of 92. An example ofsuch a material includes a sheet formed from TPU resin having partnumber A85P44304 and available from Huntsman Corporation. Other examplesof material that can be used for layer 54 include 1.0 mm thick TPUhaving a Shore D durometer value of 72 (e.g., a sheet formed from TPUresin having part number D7101 and available from Argotec, LLC) and 1.0mm thick TPU having a Shore A durometer value of 87 (e.g., a sheetformed from aromatic polyether-based TPU resin having part numberST-3685-87 and available from Argotec, LLC).

FIG. 5C1 is a top view of top layer 55 showing top surface 52 of toplayer 55. In FIG. 5C1, pockets 57 and 58 are convex structures. Medialpocket 57 is molded or otherwise formed into the sheet of top layer 55on the medial side and forms the top and upper sidewalls of medial fluidchamber 35. Lateral pocket 58 is molded or otherwise formed into thesheet of top layer 55 on the lateral side and forms the top and uppersidewalls of lateral fluid chamber 36. Layer 55 may be formed from arelatively soft and flexible TPU that allows pockets 57 and 58 to easilycollapse and expand so as to allow tops of chambers 35 and 36 to changeheight as ER fluid moves into and out of chambers 35 and 36. In at leastsome embodiments, and as explained below, top layer 55 may formed from a2-sheet lamination similar to that used for bottom layer 53.

FIG. 5C2 is a bottom view of top layer 55. Top layer 55 includes a panel82 having a bottom surface 68. In FIG. 5C2, pockets 57 and 58 areconcave structures. Layer 55 further includes a continuous conductivetrace 135 formed on bottom surface 68. Trace 135 includes a topelectrode 69 and an extension 70. Electrode 69 extends over the portionof layer 55 that forms the top of transfer channel 51. As seen in moredetail below, electrode 69 follows the path of and coincides withchannel 51. Extension 70 branches away from the path of channel 51 andtowards the rear edge of top layer 55. As explained in more detailbelow, extension 70 provides a location for terminal 24 b toelectrically connect to electrode 69. In some embodiments, conductivetrace 135 is a span of conductive ink that has been printed onto surface68. The conductive ink used to form conductive trace 135 may be the sametype of ink used to form conductive trace 116. FIG. 5C3, a partial areacross-sectional view taken from the location indicated in FIG. 5C2,shows additional details of top electrode 69 and of pocket 58. Pocket 57and other portions of top electrode may be similar. Except for anopening 66 that is part of fulcrum aperture 37, panel 82 is shown inFIG. 5C2 as a continuous sheet. In other embodiments, there may beadditional openings or gaps in panel 82 (e.g., between portions of trace135).

Panel 82 may comprise laminated inner and outer sheets of the samematerials used to create panel 81. In some embodiments, layer 55 may befabricated in the following manner. Prior to forming panel 82,conductive trace 135 is screen printed or otherwise applied to thehigher durometer face of the inner sheet. The lower durometer face ofthe inner sheet may then be placed into contact with an inner face ofthe outer sheet. The two sheets may then be laminated together byapplying heat and pressure. The laminated sheets are then thermoformedusing a mold having cavities corresponding to the shapes of pockets 57and 58. Care is taken during the thermoforming process to avoid damagingtrace 135 and to properly position trace 135 relative to pockets 57 and58. Layer 55 is then cut from the laminated and thermoformed sheets sothat conductive trace 135 is in the proper location relative to outeredges and relative to opening 66.

FIG. 5D1 shows a first assembly operation when fabricating inclineadjuster 16. As part of the first assembly operation, a first patch 139is placed over a portion of conductive trace 116. In particular, patch139 spans the width of electrode 61 in the region where branch 62 joinselectrode 61, as well as the portion of branch 62 adjacent to electrode61. In some embodiments, and as shown in FIG. 5D1, patch 139 is widerthan branch 62. Patch 139 may be, e.g., a thin strip of TPU. In someembodiments the 0.1 mm inner sheet material used for panels 81 and 82may also be used for patch 139, with the higher durometer side of thematerial placed toward trace 116. After placement of patch 139, middlelayer 54 is placed onto bottom layer 53 so that a bottom surface 67 ofmiddle layer 54 is in contact with top surface 59 of panel 81, and sothat patch 139 is interposed between top surface 59 and bottom surface67, as well as between portions of trace 116 and bottom surface 67. Insome embodiments, alignment holes (not shown) may be formed in layers53, 54, and 55 to assist in positioning during the operation of FIG. 5D1and in subsequent assembly operations.

FIG. 5D2 shows a second assembly operation when fabricating inclineadjuster 16. The left side of FIG. 5D2 shows layers 53 and 54 and patch139 after the assembly operation of FIG. 5D1. Edges of patch 139 coveredby middle layer 54 are indicated with broken lines. Electrode 61 extendsover the portion of the layer 53 top surface that forms a bottom ofchannel 51. A portion of extension 62 extends over the portion of thelayer 53 top surface that forms a bottom of access passage 39.

In the second assembly operation of FIG. 5D2, a second patch 140 isplaced over a portion of conductive trace 135. In particular, patch 140spans the width of electrode 69 in the region where branch 70 joinselectrode 69, as well as the portion of branch 70 adjacent to electrode69. In some embodiments, and as shown in FIG. 5D2, patch 140 is widerthan branch 70. Patch 140 may also be, e.g., a thin strip of TPU. Insome embodiments, patch 140 is cut from the same material used for patch139 and is positioned with the higher durometer face toward trace 135.After placement of patch 140, assembled layers 53 and 54 (withinterposed patch 139) are placed onto top layer 55 so that the bottomsurface 68 of panel 82 is in contact with top surface 63 of middle layer54, and so that patch 140 is interposed between top surface 63 andbottom surface 68, as well as between portions of trace 135 and topsurface 63.

FIG. 5D3 shows layers 53, 54, and 55 after the assembly operation ofFIG. 5D2. The positions of channel 51, channels 119 and 120, andpassages 39 and 40 are indicated with broken lines. Although not visiblein FIG. 5D3, electrode 69 extends over the portion of the layer 55bottom surface that forms a top of channel 51. A portion of extension 70extends over the portion of the layer 55 bottom surface that forms a topof access passage 40.

Layers 53, 54, and 55 and patches 139 and 140 may be bonded afterassembly by RF (radio frequency) welding. In some embodiments, amulti-step RF welding operation is performed. FIGS. 8A and 8B are topviews of two sides of an RF welding tool used in the first weldingoperation in some embodiments. FIG. 8A shows a side 401 a that contactsthe exposed bottom surface of bottom layer 53. Side 401 a includes awall 403 a that extends outward from a planar base 405 a. FIG. 8B showsa side 401 b that contacts the exposed top surface 52 of top layer 55.Side 401 b includes a wall 403 b that extends outward from a planar base405 b. Wall 403 b has a height above base 405 b that is greater than theheights of pockets 57 and 58. As can be appreciated by comparing FIGS.8A and 8B with FIG. 5D3, walls 403 a and 403 b include portions thatcorrespond to the portions of middle layer 54 that define the shape ofchannel 51. Walls 403 a and 403 b further include portions thatcorrespond to portions of middle layer 54 defining the sides of chambers35 and 36, portions that correspond to portions of middle layer 54defining passages 39 and 40, portions that correspond to portions ofmiddle layer 54 defining the region between passages 39 and 40 andchannel 51, and portions that correspond to portions of middle layer 54defining the sides of channels 119 and 120.

Sides 401 a and 401 b may be attached to opposing sides of a fixturethat is configured to press sides 401 a and 401 b together while RFfrequency electrical power is applied to sides 401 a and 401 b. Duringthe first RF welding operation, the assembly of FIG. 5D3 is placedbetween sides 401 a and 401 b, with side 401 a contacting the bottomsurface of layer 53 and side 401 b contacting the top surface of layer55, and with edges of walls 403 a and 403 b aligned with theircorresponding portions of middle layer 54. In some embodiments, sides401 a and 401 b are pressed together against the assembly (duringapplication of electrical power) so as to compress regions of theassembly between the tops of walls 403 a and 403 b to a thickness at theend of the first RF welding operation that is 85% of the thickness priorto the first RF welding operation.

Subsequently, the assembly of FIG. 5D3 is subjected to a second RFwelding operation. FIGS. 8C and 8D are top views of two sides of an RFwelding tool used in the second welding operation in some embodiments.FIG. 8C shows a side 402 a that contacts the exposed bottom surface ofbottom layer 53. Side 402 a includes a wall 404 a that extends outwardfrom a planar base 406 a. FIG. 8B shows a side 402 b that contacts theexposed top surface 52 of top layer 55. Side 402 b includes a wall 404 bthat extends outward from a planar base 406 b. Wall 404 b has a heightabove base 406 b that is greater than the heights of pockets 57 and 58.As can be appreciated by comparing FIGS. 8C and 8D with FIG. 5D3, walls404 a and 404 b include portions that correspond to the portions ofmiddle layer 54 that define the edges of chambers 35 and 36.

In the second RF welding operation, the assembly of FIG. 5D3 is placedbetween sides 402 a and 402 b, with side 402 a contacting the bottomsurface of layer 53 and side 402 b contacting the top surface of layer55, and with edges of walls 404 a and 404 b aligned with theircorresponding portions of middle layer 54. In some embodiments, sides402 a and 402 b are pressed together against the assembly (duringapplication of electrical power) so as to compress regions of theassembly between the tops of walls 404 a and 404 b to a thickness at theend of the second RF welding operation that is 65% of the thickness atthe start of the second RF welding operation.

In some embodiments, an intermediate RF welding operation may beperformed between the first and second welding operations. In some suchembodiments, tubes are inserted into the rear ends of channels 119 and120. Those tubes are then sealed in place by applying sides of an RFwelding tool around the rear ends of tabs 117 and 118. Those tubes andthe portions of tabs 117 and 118 welded to those tubes may then be cutaway after incline adjuster 16 is filled with ER fluid.

As previously indicated, incline adjuster 16 is configured forinstallation in a right shoe of a pair. An incline adjuster configuredfor installation in a left shoe of that pair may be a mirror image ofincline adjuster 16. Accordingly, sides of RF welding tools used tofabricate that left shoe incline adjuster may be mirror images of thetool sides shown in FIGS. 8A through 8D.

Additional details of the regions of incline adjuster that includepatches 139 and 140 can be found in the U.S. provisional patentapplication titled “Electrorheological Fluid Structure Having StrainRelief Element and Method of Fabrication,” U.S. application 62/260,883,filed Nov. 30, 2015, incorporated by reference herein. Various detailsof those regions are also described below in connection with FIGS. 5E11and 5E12.

At the conclusion of the RF welding operations to bond layers 53, 54,and 55 and interposed patches 139 and 140, terminals 23 b and 24 b maybe attached to portions of extensions 62 and 70 exposed in accesspassages 39 and 40. FIG. 9 is a block diagram showing steps in a methodto attach wires 23 a and 24 a according to some embodiments. In step501, annular welding operations are performed in the rear regions ofpassages 39 and 40. FIG. 10 is a partially schematic diagram showing theannular welding operation of step 501 in connection with passage 39. Asimilar operation would be performed with regard to passage 40. FIG. 10is an area cross-sectional view of the rear edge of layers 53, 54, and55 after bonding, as well as of elements 601, 602, and 603 of an annularRF welding tool. Element 603 of that tool is a round mandrel. Elements601 and 603 are plates having grooves 605 and 606 formed therein.Element 603 is inserted into passage 39. Plates 601 and 602 are thenrespectively pressed against the bottom surface of layer 53 and the topsurface 52 of layer 55 while electrical power is applied to elements601-603. That power is applied to element 603 at one polarity and toelements 601 and 602 at the opposite polarity. At the conclusion of step501, the rear portions of passages 39 and 40 are narrowed and rounded soas to better conform to wires 23 a and 24 a. In some embodiments, step501 may be omitted.

In step 503, a conductive epoxy resin and a hardener are mixed. Themixture is then injected into passages 39 and 40 so as to contactportions of extensions 62 and 70 respectively exposed within passages 39and 40. In step 505, terminal 23 b of wire 23 a is inserted into passage39 and into the epoxy mixture within passage 39. Also in step 505,terminal 24 b of wire 24 a is inserted into passage 40 and into theepoxy mixture within passage 40. In step 507, the epoxy mixture inpassages 39 and 40 is allowed to harden. Optionally, wires 23 a and 23 bmay be temporarily taped down to hold them in position until the epoxyhas hardened.

In step 509, another RF welding operation is performed. In the weldingoperation of step 509, a first plate of an RF welding tool is pressedagainst the bottom surface of layer 53, along the rear edge of layer 53,around the rear portions of passages 39 and 40. A second plate of thatRF welding tool is pressed against top surface 52 of layer 55, along therear edge of layer 55, around the rear portions of passages 39 and 40.The plates of the tool used in step 509 may have a shape generallycorresponding to crimp 151. While those plates are pressing againstlayers 53 and 55, electrical current is applied. Portions of layers 53,54, and 55 located between the plates melt and flow to form crimp 151.Portions of the insulating jackets of wires 23 a and 24 a locatedbetween the plates also melt and bond to melted portions of layers 53,54, and 55, thereby sealing one or more of those layers around wires 23a and 24 a.

After attachment of wires 23 a and 24 a, incline adjuster 16 may befilled with ER fluid through fill channel 119 and/or through fillchannel 120. After filling, channels 119 and 120 are closed and sealedby applying an RF tool to tops and bottoms of tabs 117 and 118 so as toform crimps 125 and 126. In some embodiments, filling of inclineadjuster 16 may be performed using operations described in the U.S.provisional patent application titled “Method of FillingElectrorheological Fluid Structure”, which application was filed on thesame date as the present application and is incorporated by referenceherein.

FIGS. 5E1 and 5E2 are partially schematic area cross-sectional views,taken from the locations indicated in FIG. 4A, showing portions ofincline adjuster 16 after completing the operations of FIG. 9. Thelaminated constructions of layers 53 and 55 are visible in FIGS. 5E1 and5E2. Panel 81 of layer 53 includes an inner sheet 164 bonded to an outersheet 163. Panel 82 of layer 55 similarly includes an inner sheet 162bonded to an outer sheet 161. As indicated above, sheets 161 and 163 maybe formed from the same material in some embodiments, as may sheets 162and 164.

Details of wires 23 a and 24 a are also visible in FIGS. 5E1 and 5E2. Asseen in FIG. 5E1, wire 23 a includes a conductor 23 c covered by aninsulating jacket 23 d. Terminal 23 b is an exposed portion of conductor23 c. As seen in FIG. 5E2, wire 24 a includes a conductor 24 c coveredby an insulating jacket 24 d. Terminal 24 b is an exposed portion ofconductor 24 c.

As seen in FIG. 5E1, a hardened mass 153 of conductive epoxy bondsterminal 23 b to a portion of extension 62. Conductor 23 c is therebyplaced into electrical communication with conductive trace 116,including bottom electrode 61 (not visible in FIG. 5E1). Although FIG.5E1 shows a gap in passage 39, in some embodiments a hardened conductiveepoxy mass may completely fill passage 39. A bonding region ofinsulating jacket 23 d located within passage 39 is welded to a bondingregion of layer 54 forming the walls of passage 39. As seen in FIG. 5E3,an area-cross sectional view taken from the location indicated in FIG.5E1, middle layer 54 completely surrounds jacket 23 d.

The attachment of wire 24 a has a similar structure, as seen in FIG.5E2. a hardened mass 154 of conductive epoxy bonds terminal 24 b to aportion of extension 70, thereby placing conductor 24 c into electricalcommunication with conductive trace 135, including top electrode 69 (notvisible in FIG. 5E2). Similar to FIG. 5E1, FIG. 5E2 shows a gap inpassage 40. In some embodiments a hardened conductive epoxy mass maycompletely fill passage 40. A bonding region of insulating jacket 24 dlocated within passage 40 is welded to a bonding region of layer 54forming the walls of passage 40. As seen in FIG. 5E4, an area-crosssectional view taken from the location indicated in FIG. 5E2, middlelayer 54 completely surrounds jacket 24 d.

In some embodiments, an attached wire may have a position different fromthat shown in FIGS. 5E3 and 5E4. FIGS. 5E5 through 5E10 are partiallyschematic area cross-sectional views, taken from locations similar tothat indicated in FIG. 5E1 for FIG. 5E3, of attached wires according toadditional embodiments. In some embodiments, and as shown in FIGS. 5E5through 5E7, jacket 23 d of wire 23 a may contact upper layer 55 (FIGS.5E5 and 5E7) and/or lower layer 53 (FIGS. 5E6 and 5E7). In someembodiments, and as shown in FIGS. 5E8 through 5E10, that contact may bemore extensive. Upper layer 55 and/or lower layer 53 may partiallyconform to jacket 23 d. In the embodiments of FIGS. 5E5 through 5E10,jacket 23 d may be bonded to upper layer 55 and/or lower layer 53 wherecontacted, as well as to middle layer 54. Although FIGS. 5E5 through5E10 only show wire 23 a, wire 24 b may also have an attachmentconfiguration such as shown in FIGS. 5E5 through 5E10. In someembodiments in which the wire attachment has a configuration such asthat shown in one of FIGS. 5E8 through 5E10, one or both sides thewelding tool used to perform step 509 (FIG. 9) may be modified conformto and help form an external contour of layer 53 or layer 55 such as isshown in FIGS. 5E8 through 5E10.

For convenience, the portion of a wire insulating jacket (e.g., theportion of jacket 23 d or of jacket 24 d bonded to layers 54, or tolayers 54, 53, and/or 55) that is bonded to a polymeric housing (e.g.,the housing of incline adjuster 16) through RF welding may be referredto as a “jacket bonding region.” Similarly, the portion of a polymerichousing (e.g., the portion of layer 54, or of layers 54, 53 and/or 55,bonded to jacket 23 d or to jacket 24 d) may be referred to as a“housing bonding region.” To improve bonding between a wire and ahousing and to better seal that housing, at least the jacket bondingregion of a wire's insulation and at least the housing bonding region ofa polymeric housing may be formed from a common type of polymer. As usedherein, a “type” of polymer refers to a group of polymers that arechemically very similar. Individual polymers within a type may varysomewhat, e.g., by having different durometer values. In someembodiments, at least the jacket bonding region of a wire's insulationand at least the housing bonding region of a polymeric housing may beformed from a common type of thermoplastic elastomer. Types ofthermoplastic elastomers include thermoplastic polyurethane (TPU),thermoplastic styrene, thermoplastic copolyester, thermoplasticpolyamide, thermoplastic polyolefins, and thermoplastic vulcanizates. Insome embodiments, at least the jacket bonding region of a wire'sinsulation and at least the housing bonding region of a polymerichousing may be formed from a TPU. For example, jacket 23 d and jacket 24d could be extruded TPU. The TPU of a jacket bonding region may differ(e.g., in durometer value) from the TPU(s) in a housing bonding region.

Although the housing bonding region of a polymeric housing may be madeof the same material used in other portions of a housing (e.g., as inthe case of middle layer 54 according to some embodiments), this neednot be the case. As but one example, a housing or component thereofcould be formed from one type of polymer in a housing bonding region andof another type of polymer in a separate region.

FIGS. 5E11 and 5E12 are partially schematic area cross-sectional views,taken from the locations indicated in FIG. 4A, showing incline adjuster16 after assembly. As indicated above, various regions of inclineadjuster 16 may be compressed during RF welding portions of the assemblyprocess. No attempt is made to accurately depict the compressedcross-sectional profile in FIGS. 5E11 and 5E12.

As seen in FIGS. 5E11 and 5E12, ER fluid 121 fills transfer channel 51.Electrodes 61 and 69 are located at the top and bottom, respectively, ofchannel 51. Although FIGS. 5E11 and 5E12 shows edges of electrodes 61and 69 located near edges of opening 129, in some embodiments electrodes61 and 69 may be formed wider so as to extend further under and overlayer 54 throughout some or all of the length of transfer channel 51.

As seen in FIG. 5E11, extension 62 is connected to bottom electrode 61and extends from transfer channel 51 to access passage 39. Inparticular, extension 62 is located between bottom surface 67 of layer54 and top surface 59 of panel 81. As indicated above, layer 54 tends toextrude into transfer channel 51 during RF welding operations. Thisextrusion may tend to tear portions of trace 116 at the interfacebetween layer 54 and layer 53 near edges of opening 129. In manyportions of electrode 61, such tearing is not a problem. At the junctionof electrode 61 and extension 62, however, such tearing may result in aloss of the electrical connection between electrode 61 and the portionof extension 62 to which terminal 23 b is connected. Patch 139 is placedbetween layers 54 and 53 to prevent such tearing. As seen in FIG. 5E11,patch 139 spans channel 51 in the region of the connection betweenelectrode 61 and extension 62. When layer 54 extrudes into channel 51during RF welding, patch 139 provides strain relief. In particular,patch 139 absorbs the shear stress and prevents transfer of all of thatshear stress to the region of trace 116 forming the connection betweenelectrode 61 and extension 62. Similarly, by extending along the lengthof extension 62 between channel 51 and passage 39 and into passage 39,patch 139 prevents tearing of extension 62 at the interface betweenlayers 53 and 54 in passage 39.

As seen in FIG. 5E12, extension 70 is connected to top electrode 69 andextends from transfer channel 51 to access passage 40. In particular,extension 70 is located between bottom surface 68 of panel 82 and topsurface 63 of layer 54. Patch 140 spans channel 51 in the region of theconnection between electrode 69 and extension 70. Patch 140 furtherextends along the length of extension 70, between channel 51 and passage40, and into passage 40. Similar to patch 139, patch 140 provides strainrelief and prevents tearing of trace 135 in the region of trace 135forming the connection between electrode 69 and extension 70 or in theregion of extension 70 at the interface between layers 54 and 55 inpassage 40.

FIG. 6 is a block diagram showing electrical system components of shoe10. Individual lines to or from blocks in FIG. 6 represent signal (e.g.,data and/or power) flow paths and are not necessarily intended torepresent individual conductors. Battery pack 13 includes a rechargeablelithium ion battery 101, a battery connector 102, and a lithium ionbattery protection IC (integrated circuit) 103. Protection IC 103detects abnormal charging and discharging conditions, controls chargingof battery 101, and performs other conventional battery protectioncircuit operations. Battery pack 13 also includes a USB (universalserial bus) port 104 for communication with controller 47 and forcharging battery 101. A power path control unit 105 controls whetherpower is supplied to controller 47 from USB port 104 or from battery101. A Reset button 106 activates or deactivates controller 47 andbattery pack 13. An LED (light emitting diode) 107 indicates whether thecontroller is ON and the state of the electrical field. Theabove-described individual elements of battery pack 13 may beconventional and commercially available components that are combined andused in the novel and inventive ways described herein.

Controller 47 includes the components housed on PCB 46, as well asconverter 45. In other embodiments, the components of PCB 46 andconverter 45 may be included on a single PCB, or may be packaged in someother manner. Controller 47 includes a processor 110, a memory 111, aninertial measurement unit (IMU) 113, and a low energy wirelesscommunication module 112 (e.g., a BLUETOOTH communication module).Memory 111 stores instructions that may be executed by processor 110 andmay store other data. Processor 110 executes instructions stored bymemory 111 and/or stored in processor 110, which execution results incontroller 47 performing operations such as are described herein and inU.S. patent application Ser. No. 14/725,218, titled “Footwear Includingan Incline Adjuster” and filed May 29, 2015, which application (in itsentirety) is incorporated by reference herein. As used herein,instructions may include hard-coded instructions and/or programmableinstructions.

IMU 113 may include a gyroscope and an accelerometer and/or amagnetometer. Data output by IMU 113 may be used by processor 110 todetect changes in orientation and motion of shoe 10, and thus of a footwearing shoe 10. As explained in more detail below, processor 10 may usesuch information to determine when an incline of a portion of shoe 10should change. Wireless communication module 112 may include an ASIC(application specific integrated circuit) and be used to communicateprogramming and other instructions to processor 110, as well as todownload data that may be stored by memory 111 or processor 110.

Controller 47 includes a low-dropout voltage regulator (LDO) 114 and aboost regulator/converter 115. LDO 114 receives power from battery pack13 and outputs a constant voltage to processor 110, memory 111, wirelesscommunication module 112, and IMU 113. Boost regulator/converter 115boosts a voltage from battery pack 13 to a level (e.g., 5 volts) thatprovides an acceptable input voltage to converter 45. Converter 45 thenincreases that voltage to a much higher level (e.g., 5000 volts) andsupplies that high voltage across electrodes 61 and 69 of inclineadjuster 16. Boost regulator/converter 115 and converter 45 are enabledand disabled by signals from processor 110. Controller 47 furtherreceives signals from medial FSR 31 and from lateral FSR 32. Based onthose signals from FSRs 31 and 32, processor 110 determines whetherforces from a wearer foot on medial fluid chamber 35 and on lateralfluid chamber 36 are creating a pressure within chamber 35 that ishigher than a pressure within chamber 36, or vice versa.

The above-described individual elements of controller 47 may beconventional and commercially available components that are combined andused in the novel and inventive ways described herein. Moreover,controller 47 is physically configured, by instructions stored in memory111 and/or processor 110, to perform the herein described novel andinventive operations in connection with controlling transfer of fluidbetween chambers 35 and 36 so as to adjust the incline of the forefootportion of the shoe 10 footbed 14.

FIGS. 7A through 7D are partially schematic area cross-sectionaldiagrams showing operation of incline adjuster 16, according to someembodiments, when going from a minimum incline condition to a maximumincline condition. In the minimum incline condition, an incline angle αof the top plate relative to the bottom plate has a value of α_(min)representing a minimum amount of incline sole structure 12 is configuredto provide in the forefoot region. In some embodiments, α_(min)=0°. Inthe maximum incline condition, the incline angle α has a value ofα_(max) representing a maximum amount of incline sole structure 12 isconfigured to provide. In some embodiments, α_(max) is at least 5°. Insome embodiments, α_(max)=10°. In some embodiments, α_(max) may begreater than 10°.

In FIGS. 7A-7D, bottom plate 29, incline adjuster 16, top plate 41, FSR31, FSR 32, and fulcrum element 34 are represented, but other elementsare omitted for simplicity. FIG. 7E is a top view of incline adjuster 16(in a minimum incline condition) and bottom plate 29 showing theapproximate locations of the sectioning lines corresponding to the viewsof FIGS. 7A-7D. Top plate 41 is omitted from FIG. 7E, but the peripheraledge of top plate 41 would generally coincide with that of bottom plate29 if top plate 41 were included In FIG. 7E. Although fulcrum element 34would not appear in an area cross-section according to the section linesof FIG. 7E, the general position of fulcrum element 34 relative to themedial and lateral sides of other elements in FIGS. 7A-7D is indicatedwith broken lines.

Also indicated in FIGS. 7A through 7D are a lateral side stop 123 and amedial side stop 122. Medial side stop 122 supports the medial side oftop plate 41 when incline adjuster 16 and top plate 41 are in themaximum incline condition. Lateral side stop 123 supports the lateralside of top plate 41 when incline adjuster 16 and top plate 41 are inthe minimum incline condition. Lateral side stop 123 prevents top plate41 from tilting toward the lateral side. Because runners proceed arounda track in a counterclockwise direction during a race, a wearer of shoe10 will be turning to his or her left when running on curved portions ofa track. In such a usage scenario, there would be no need to incline thefootbed of a right shoe sole structure toward the lateral side. In otherembodiments, however, a sole structure may be tiltable to either medialor lateral side.

In some embodiments, a left shoe from a pair that includes shoe 10 maybe configured in a slightly different manner from what is shown in FIGS.7A-7D. For example, a medial side stop may be at a height similar tothat of lateral side stop 123 of shoe 10, and a lateral side stop may beat a height similar to that of medial side stop 122 of shoe 10. In suchembodiments, the top plate of the left shoe moves between a minimumincline condition and maximum incline condition in which the top plateis inclined to the lateral side.

The locations of lateral side stop 123 and of medial side stop 122 arerepresented schematically in FIGS. 7A-7D, and are not shown in previousdrawing figures. In some embodiments, lateral side stop 123 may beformed as a rim on the lateral side or edge of bottom plate 29.Similarly, medial side stop 122 my be formed as a rim on the medial sideor edge of bottom plate 29.

FIG. 7A shows incline adjuster 16 when top plate 41 is in a minimumincline condition. Shoe 10 may be configured to place top plate 41 intothe minimum incline condition when a wearer of shoe 10 is standing or isin starting blocks about to begin a race, or when the wearer is runninga straight portion of a track. In FIG. 7A, controller 47 is maintainingthe voltage across electrodes 61 and 69 at one or more flow-inhibitingvoltage levels (V=V_(fi)). In particular, the voltage across electrodes61 and 69 is high enough to generate an electrical field having astrength sufficient to increase the viscosity of ER fluid 121 intransfer channel 51 to a viscosity level that prevents flow out of orinto chambers 35 and 36. In some embodiments, a flow-inhibiting voltagelevel V_(fi) is a voltage sufficient to create a field strength betweenelectrodes 61 and 69 of between 3 kV/mm and 6 kV/mm. In FIGS. 7A through7D, light stippling is used to indicate ER fluid 121 having a viscositythat is at a normal viscosity level, i.e., unaffected by an electricalfield. Dense stippling is used to indicate ER fluid 121 in which theviscosity has been raised to a level that blocks flow through channel51. Because ER fluid 121 cannot flow through channel 51 under theconditions shown in FIG. 7A, the incline angle α of top plate 41 doesnot change if the wearer of shoe 10 shifts weight between medial andlateral sides of shoe 10.

FIG. 7B shows incline adjuster 16 soon after controller 47 hasdetermined that top plate 41 should be placed into the maximum inclinecondition, i.e., inclined to α=α_(max). In some embodiments, controller47 makes such a determination based on a number of steps taken by theshoe 10 wearer. Upon determining that top plate 41 should be inclined toα_(max), controller 47 determines if the foot wearing shoe 10 is in aportion of the wearer gait cycle in which shoe 10 is in contact with theground. Controller 47 also determines if a difference ΔP_(M-L) betweenthe pressure P_(M) of ER fluid 121 in medial side chamber 35 and thepressure P_(L) of ER fluid 121 in lateral side chamber 36 is positive,i.e., if P_(M)−P_(L) is greater than zero. If shoe 10 is in contact withthe ground and ΔP_(M-L) is positive, controller 47 reduces the voltageacross electrodes 61 and 69 to a flow-enabling voltage level V_(fe). Inparticular, the voltage across electrodes 61 and 69 is reduced to alevel that is low enough to reduce the strength of the electrical fieldin transfer channel 51 so that the viscosity of ER fluid 121 in transferchannel 51 is at a normal viscosity level.

Upon reducing the voltage across electrodes 61 and 69 to a V_(fe) level,the viscosity of ER fluid 121 in channel 51 drops. ER fluid 121 thenbegins flowing out of chamber 35 and into chamber 36. This allows themedial side of top plate 41 to begin moving toward bottom plate 29, andthe lateral side of top plate 41 to begin moving away from bottom plate29. As a result, the incline angle α begins to increase from α_(min).

In some embodiments, controller 47 determines if shoe 10 is in a stepportion of the gait cycle and in contact with the ground based on datafrom IMU 113. In particular, IMU 113 may include a three-axisaccelerometer and a three-axis gyroscope. Using data from theaccelerometer and gyroscope, and based on known biomechanics of a runnerfoot, e.g., rotations and accelerations in various directions duringdifferent portions of a gait cycle, controller 47 can determine whetherthe right foot of the shoe 10 wearer is stepping on the ground.Controller 47 may determine if ΔP_(M-L) is positive based on the signalsfrom FSR 31 and FSR 32. Each of those signals corresponds to magnitudeof a force from a wearer foot pressing down on the FSR. Based on themagnitudes of those forces and on the known dimensions of chambers 35and 36, controller 47 can correlate the values of signals from FSR 31and FSR 32 to a magnitude and a sign of ΔP_(M-L).

FIG. 7C shows incline adjuster 16 very soon after the time associatedwith FIG. 7B. In FIG. 7C, top plate 41 has reach the maximum inclinecondition. In particular, the incline angle α of top plate 41 hasreached α_(max). Medial stop 122 prevents incline angle α from exceedingα_(max). FIG. 7D shows incline adjuster 16 very soon after the timeassociated with FIG. 7C. In FIG. 7D, controller 47 has raised thevoltage across electrodes 61 and 69 to a flow-inhibiting voltage levelV_(fi). This prevents further flow through transfer channel 51 and holdstop plate 41 in the maximum incline condition. During a normal gaitcycle, downward force of a right foot on a shoe is initially higher onthe lateral side as the forefoot rolls to the medial side. If flowthrough channel 51 were not prevented, the initial downward force on thelateral side of the wearer right foot would decrease incline angle α.

In some embodiments, a shoe may include an incline adjuster and othercomponents that are configured to incline a different portion of a shoefootbed. As but one example, a basketball shoe may include an inclineadjuster similar to incline adjuster 16, but having one chamberpositioned in a medial midfoot or heel region, and another chamberpositioned in a lateral midfoot or heel region, and with shapes of thechambers modified to match those positions. A controller of such a shoecould be configured to perform operations similar to those describedabove upon determining that a wearer's body position corresponds to aneed to incline the midfoot and/or heel, and upon determining that suchinclination is no longer needed. When cutting to the left, for example,a right shoe having a midfoot and heel region inclined medially couldprovide additional support and stability. A controller could beconfigured to determine that a cutting motion is occurring based onposition and/or movement of the wearer's torso, and/or based on a suddenincrease in pressure on a medial side of the shoe, and/or based onsensors located within an upper that indicate the heel region has tiltedrelative to the forefoot region.

A controller need not be located within a sole structure. In someembodiments, for example, some or all components of a controller couldbe located with the housing of a battery assembly such as batteryassembly 13 and/or in another housing positioned on a footwear upper.

As can be appreciated from the above, incline adjuster 16 is a structureholding an ER fluid. Other embodiments include other structures thathold or that are configured to hold ER fluid and that have featuressimilar to those described in connection with incline adjuster 16, butthat may differ from incline adjuster 16 in one or more respects. Suchstructures, referred to herein as ER fluid structures for convenience,may be used in foot wear or in other applications.

In some embodiments, an ER fluid structure may include chambers havingsizes and/or shapes different from those shown in above. Similarly, atransfer channel may have other sizes and/or shapes.

In some embodiments, an ER fluid structure may only have a singlechamber, with one end of a transfer channel left open. That opentransfer channel may subsequently be connected to another structurehaving an ER fluid reservoir or chamber, to a pump configured totransfer ER fluid from a separate reservoir or chamber, or to some othercomponent.

In some embodiments, and ER fluid structure may not include chambers.For example, such a structure could be similar to the central portion ofincline adjuster 16 that includes transfer channel 51 and accesspassages 39 and 40. Instead of connecting to chambers within thestructure, however, the transfer channel ends may be open andconnectable to separate components. Such a structure could be used,e.g., as a valve in an ER fluid system.

The foregoing description of embodiments has been presented for purposesof illustration and description. The foregoing description is notintended to be exhaustive or to limit embodiments of the presentinvention to the precise form disclosed, and modifications andvariations are possible in light of the above teachings or may beacquired from practice of various embodiments. The embodiments discussedherein were chosen and described in order to explain the principles andthe nature of various embodiments and their practical application toenable one skilled in the art to utilize the present invention invarious embodiments and with various modifications as are suited to theparticular use contemplated. Any and all combinations, subcombinationsand permutations of features from herein-described embodiments are thewithin the scope of the invention. In the claims, a reference to apotential or intended wearer or a user of a component does not requireactual wearing or using of the component or the presence of the weareror user as part of the claimed invention.

The invention claimed is:
 1. A footwear sole component comprising: apolymeric housing having a fluid transfer channel defined therein; afirst conductive trace at least partially coinciding with the fluidtransfer channel; and the polymeric housing further comprising a firstaccess passage containing a first wire having a first conductorsurrounded by a first insulating jacket, wherein the first conductor isin electrical communication with the first conductive trace, wherein ajacket bonding region of the first insulating jacket located within thefirst access passage is welded to a corresponding housing bonding regionof the polymeric housing, and wherein the jacket bonding region and thehousing bonding region are formed from a polymer; wherein the firstconductive trace comprises a first electrode that follows a path of thefluid transfer channel and a first extension that branches away from thepath of the fluid transfer channel through the first access passage, andwherein the first conductor is attached to a portion of the firstextension branching from the fluid transfer channel.
 2. The footwearsole component of claim 1, wherein the jacket bonding region and thehousing bonding region are formed from a thermoplastic elastomer.
 3. Thefootwear sole component of claim 1, wherein the jacket bonding regionand the housing bonding region are formed from thermoplasticpolyurethane.
 4. The footwear sole component of claim 1, wherein thepolymeric housing further comprises a first chamber in fluidcommunication with the fluid transfer channel.
 5. The footwear solecomponent of claim 4, wherein the first chamber and the fluid transferchannel are filled with electrorheological fluid, and wherein the firstchamber has a height that varies in response to transfer of theelectrorheological fluid into and out of the first chamber.
 6. Thefootwear sole component of claim 5, wherein the polymeric housingfurther comprises a second chamber in fluid communication with the fluidtransfer channel, wherein the second chamber is filled with theelectrorheological fluid, and wherein the second chamber has a heightthat varies in response to transfer of the electrorheological fluid intoand out of the second chamber.
 7. The footwear sole component of claim1, wherein the polymeric housing comprises a first polymeric layerhaving a surface forming a side of the fluid transfer channel, the firstconductive trace forming at least a portion of the first polymeric layersurface, the polymeric housing comprises a second polymeric layer havinga first surface, at least a portion of the second polymeric layer firstsurface being bonded to the first polymeric layer surface, and walls ofthe fluid transfer channel are defined in the second polymeric layer. 8.The footwear sole component of claim 7, wherein the polymeric housingcomprises a third polymeric layer having a surface forming a side of thefluid transfer channel, and at least a portion of a second surface ofthe second layer is bonded to the third polymeric layer surface.
 9. Thefootwear sole component of claim 8, further comprising: a secondconductive trace forming at least a portion of the third polymeric layersurface; and the polymeric housing further comprising a second accesspassage containing a second wire having a second conductor surrounded bya second insulating jacket, wherein the second conductor is inelectrical communication with the second conductive trace, wherein asecond jacket bonding region of the second jacket is welded to a secondhousing bonding region of the polymeric housing, and wherein the secondjacket bonding region and the second housing bonding region are formedfrom a polymer.
 10. The footwear sole component of claim 9, wherein thefirst extension that branches away from the path of the fluid transferchannel passes across the second polymeric layer first surface.
 11. Thefootwear sole component of claim 8, wherein the first polymeric layer,the second polymeric layer, and the third polymeric layer are formedfrom thermoplastic polyurethane.
 12. A sole structure for an article offootwear, the sole structure incorporating the footwear sole componentaccording to claim
 1. 13. An article of footwear incorporating thefootwear sole component according to claim 1.